1. Field of the Invention
The present invention relates to deformation of generally thin walled bodies, particularly thin walled containers or tube-form bodies which may be of cylindrical or other form.
The invention is particularly suited to embossing of thin walled metallic bodies (particularly aluminium containers) by embossing or the like. More specifically the invention may be used in processes such as registered embossing of thin walled bodies, particularly registered embossing of containers having pre-applied (pre-printed) surface decoration.
2. State of the Art
It is known to be desirable to deform by embossing or the like the external cylindrical walls of metallic containers such as aluminium containers. In particular attempts have been made to emboss the walls of containers at predetermined locations to complement a printed design on the external surface of such a container. In such techniques it is important to coordinate the embossing tooling with the preprinted design on the container wall. Prior art proposals disclose the use of a scanning system to identify the position of the container relative to a datum position and reorientation of the container to conform to the datum position.
Prior art embossing techniques and apparatus are disclosed in, for example, WO-A-9803280, WO-A-9803279, WO-A-9721505 and WO-A-9515227. Commonly in such techniques the container is loaded into an internal tool which acts to support the container and also co-operate with an external tool in order to effect embossing. Such systems have disadvantages, as will become apparent from the following.
An improved technique has now been devised.